Maxitrol MR212G-2424 Valve and Regulator

The Maxitrol MR212G-2424 is a specialized 3-inch NPT modulating gas valve and regulator engineered specifically for direct-fired burners operating under negative pressure conditions. As a cornerstone of the Selectra electronic gas flame modulation system, this heavy-duty component eliminates the need for complex mechanical linkages or motor-driven butterfly valves, providing instantaneous and non-fluctuating temperature control. Designed for "pull-through" industrial systems, it utilizes a precision-engineered counter spring to maintain a positive seal against the downward force of negative pressure, ensuring the gas pressure regulator stays closed when inactive.

This industrial gas control handles an inlet pressure max of 5 PSI and is factory set for applications up to -1.5 inches w.c., though it remains field-adjustable up to -3.5 inches w.c. for high-demand HVAC burner manifold setups. An integrated adjustable bypass allows for a consistent minimum firing rate during low-fire operations, maintaining stable combustion even when the main valve is closed. By synthesizing modulation and regulation into a single unit, the Maxitrol MR212G series simplifies the fuel train while delivering the precise thermal output required for high-capacity process heating and stabilized area heating applications.

• Dual-Function Design: Integrates both modulation and pressure regulation into one 3-inch NPT body, reducing piping complexity and potential leak points.
• Negative Pressure Compatibility: Specifically built with a counter-spring mechanism for negative pressure burners, preventing unintended gas flow in pull-through systems.
• Precise Flame Control: Enables infinite, continuous flame adjustment without the lag or maintenance requirements of mechanical actuators.
• Field Adjustability: Allows technicians to fine-tune burner manifold pressure settings up to -3.5 inches w.c. to match specific site requirements.
• High Capacity Performance: Rated for large-scale industrial heating, accommodating up to 5 PSI inlet pressure and 30,000 CFH capacities.

How does this valve handle negative pressure without leaking?
The MR212G-2424 uses a dedicated internal counter spring designed to counteract the suction of pull-through burners. This ensures the modulating gas valve remains firmly closed until the solenoid applies enough magnetic force to the plunger to overcome the spring and allow gas flow.

Can this unit be used with Liquefied Petroleum (LP) gas?
While the standard MR212G is typically set for natural gas, "H" suffix models within this series are specifically designated for LP gas conversion and other specialized gas mixtures. Always verify the specific model suffix for non-natural gas applications.

Is an upstream regulator required with the MR212 series?
Unlike the M411 or M511 series, the Maxitrol MR212G-2424 features an integral pressure regulator. However, if the source pressure exceeds the 5 PSI max inlet pressure rating, an additional step-down regulator must be installed upstream to protect the valve's diaphragm.

This item is not eligible for free shipping.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.